Field of the Invention
The present invention relates to a light-emitting diode having a novel structure and an electronic apparatus including the same.
Background Art
In general, a light-emitting diode includes two electrodes facing each other and a light-emitting layer including a light-emitting compound interposed between the electrodes. When current flows between the electrodes, the light-emitting compound produces light. A display device using the light-emitting diode does not need a separate light source device, and thus may decrease the weight, size or thickness of the display device. Further, the display device using the light-emitting diode has an advantage in that the viewing angle, the contrast ratio, the color reproducibility, and the like are excellent and power consumption is low as compared to a display device using a backlight and a liquid crystal.
The materials used as an organic material layer of an organic light-emitting diode among the light-emitting diodes may be classified into a light-emitting material, a hole injection material, a hole transport material, an electron transport material, an electron injection material, and the like according to the function. The light-emitting materials may be divided into a polymer-type and a low molecular weight-type according to the molecular weight, and may be divided into blue, green, red light-emitting materials, and the like according to the light-emitting color.
When a single material is used as a light-emitting material, there may occur a problem in that the maximum light-emitting wavelength is moved into the long wavelength by the interaction between molecules, the color purity is reduced, or efficiency of the diode is lowered by the light-emitting reducing effect. In order to complement the problem, a light-emitting layer composed of a host/dopant system may be applied to the light-emitting diode. An exciton formed in the light-emitting layer is transferred to a dopant by using a host material, which is a main material forming the light-emitting layer, and a small amount of the dopant having an energy band gap lower than that of the host, so that the light-emitting diode may efficiently emit light.
However, the light-emitting diode still has a problem in that light emission has a lifespan and the power efficiency is low. In order to solve these problems, various compounds have been developed as a material for the light-emitting diode, but there is a limitation in manufacturing a light-emitting diode which satisfies both the light emission lifespan and the power efficiency.